package com.alibaba.cobar.server.parser;

import com.alibaba.cobar.server.util.ParseUtil;

/**
 * @author xianmao.hexm 2011-5-7 下午01:22:57
 */
public final class ServerParseSet {

    public static final int OTHER                    = -1;
    public static final int AUTOCOMMIT_ON            = 1;
    public static final int AUTOCOMMIT_OFF           = 2;
    public static final int TX_READ_UNCOMMITTED      = 3;
    public static final int TX_READ_COMMITTED        = 4;
    public static final int TX_REPEATED_READ         = 5;
    public static final int TX_SERIALIZABLE          = 6;
    public static final int NAMES                    = 7;
    public static final int CHARACTER_SET_CLIENT     = 8;
    public static final int CHARACTER_SET_CONNECTION = 9;
    public static final int CHARACTER_SET_RESULTS    = 10;
    public static final int SQL_MODE                 = 11;

    /**
     * 完全禁止跨库事务
     */
    public static final int TX_POLICY_1              = 12;

    /**
     * autocommit=true时跨库写在多个库上commit
     */
    public static final int TX_POLICY_2              = 13;

    /**
     * 禁止跨库写，允许跨库读
     */
    public static final int TX_POLICY_3              = 14;

    /**
     * policy_2的基础上允许跨库读
     */
    public static final int TX_POLICY_4              = 15;

    /**
     * 完全允许跨库事务
     */
    public static final int TX_POLICY_5              = 16;

    public static final int AT_VAR                   = 17;

    public static int parse(String stmt, int offset) {
        int i = offset;
        for (; i < stmt.length(); i++) {
            switch (stmt.charAt(i)) {
                case ' ':
                case '\r':
                case '\n':
                case '\t':
                    continue;
                case '/':
                case '#':
                    i = ParseUtil.comment(stmt, i);
                    continue;
                case 'A':
                case 'a':
                    return autocommit(stmt, i);
                case 'C':
                case 'c':
                    return characterSet(stmt, i, 0);
                case 'N':
                case 'n':
                    return names(stmt, i);
                case 'S':
                case 's':
                    return sCheck(stmt, i);
                case 'T':
                case 't':
                    return transaction(stmt, i);
                case '@':
                    /* // SET @PARAM = */
                    return AT_VAR;
                default:
                    return OTHER;
            }
        }
        return OTHER;
    }

    // SET AUTOCOMMIT(' '=)
    private static int autocommit(String stmt, int offset) {
        if (stmt.length() > offset + 9) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            char c9 = stmt.charAt(++offset);
            if ((c1 == 'U' || c1 == 'u') && (c2 == 'T' || c2 == 't') && (c3 == 'O' || c3 == 'o')
                && (c4 == 'C' || c4 == 'c') && (c5 == 'O' || c5 == 'o') && (c6 == 'M' || c6 == 'm')
                && (c7 == 'M' || c7 == 'm') && (c8 == 'I' || c8 == 'i') && (c9 == 'T' || c9 == 't')) {
                while (stmt.length() > ++offset) {
                    switch (stmt.charAt(offset)) {
                        case ' ':
                        case '\r':
                        case '\n':
                        case '\t':
                            continue;
                        case '=':
                            return autocommitValue(stmt, offset);
                        default:
                            return OTHER;
                    }
                }
            }
        }
        return OTHER;
    }

    private static int autocommitValue(String stmt, int offset) {
        for (;;) {
            offset++;
            if (stmt.length() <= offset) {
                return OTHER;
            }
            switch (stmt.charAt(offset)) {
                case ' ':
                case '\r':
                case '\n':
                case '\t':
                    continue;
                case '1':
                    if (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset))) {
                        return AUTOCOMMIT_ON;
                    } else {
                        return OTHER;
                    }
                case '0':
                    if (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset))) {
                        return AUTOCOMMIT_OFF;
                    } else {
                        return OTHER;
                    }
                case 'O':
                case 'o':
                    return autocommitOn(stmt, offset);
                default:
                    return OTHER;
            }
        }
    }

    private static int autocommitOn(String stmt, int offset) {
        if (stmt.length() > ++offset) {
            switch (stmt.charAt(offset)) {
                case 'N':
                case 'n':
                    if (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset))) {
                        return AUTOCOMMIT_ON;
                    } else {
                        return OTHER;
                    }
                case 'F':
                case 'f':
                    return autocommitOff(stmt, offset);
                default:
                    return OTHER;
            }
        }
        return OTHER;
    }

    // SET AUTOCOMMIT = OFF
    private static int autocommitOff(String stmt, int offset) {
        if (stmt.length() > ++offset) {
            switch (stmt.charAt(offset)) {
                case 'F':
                case 'f':
                    if (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset))) {
                        return AUTOCOMMIT_OFF;
                    } else {
                        return OTHER;
                    }
                default:
                    return OTHER;
            }
        }
        return OTHER;
    }

    // SET NAMES' '
    private static int names(String stmt, int offset) {
        if (stmt.length() > offset + 5) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            if ((c1 == 'A' || c1 == 'a') && (c2 == 'M' || c2 == 'm') && (c3 == 'E' || c3 == 'e')
                && (c4 == 'S' || c4 == 's') && stmt.charAt(++offset) == ' ') {
                return (offset << 8) | NAMES;
            }
        }
        return OTHER;
    }

    // SET CHARACTER_SET_
    private static int characterSet(String stmt, int offset, int depth) {
        if (stmt.length() > offset + 14) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            char c9 = stmt.charAt(++offset);
            char c10 = stmt.charAt(++offset);
            char c11 = stmt.charAt(++offset);
            char c12 = stmt.charAt(++offset);
            char c13 = stmt.charAt(++offset);
            char c14 = stmt.charAt(++offset);
            if ((c1 == 'H' || c1 == 'h') && (c2 == 'A' || c2 == 'a') && (c3 == 'R' || c3 == 'r')
                && (c4 == 'A' || c4 == 'a') && (c5 == 'C' || c5 == 'c') && (c6 == 'T' || c6 == 't')
                && (c7 == 'E' || c7 == 'e') && (c8 == 'R' || c8 == 'r') && (c9 == '_') && (c10 == 'S' || c10 == 's')
                && (c11 == 'E' || c11 == 'e') && (c12 == 'T' || c12 == 't') && (c13 == '_')) {
                switch (c14) {
                    case 'R':
                    case 'r':
                        return characterSetResults(stmt, offset);
                    case 'C':
                    case 'c':
                        return characterSetC(stmt, offset);
                    default:
                        return OTHER;
                }
            }
        }
        return OTHER;
    }

    // SET CHARACTER_SET_RESULTS =
    private static int characterSetResults(String stmt, int offset) {
        if (stmt.length() > offset + 6) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            if ((c1 == 'E' || c1 == 'e') && (c2 == 'S' || c2 == 's') && (c3 == 'U' || c3 == 'u')
                && (c4 == 'L' || c4 == 'l') && (c5 == 'T' || c5 == 't') && (c6 == 'S' || c6 == 's')) {
                while (stmt.length() > ++offset) {
                    switch (stmt.charAt(offset)) {
                        case ' ':
                        case '\r':
                        case '\n':
                        case '\t':
                            continue;
                        case '=':
                            while (stmt.length() > ++offset) {
                                switch (stmt.charAt(offset)) {
                                    case ' ':
                                    case '\r':
                                    case '\n':
                                    case '\t':
                                        continue;
                                    default:
                                        return (offset << 8) | CHARACTER_SET_RESULTS;
                                }
                            }
                            return OTHER;
                        default:
                            return OTHER;
                    }
                }
            }
        }
        return OTHER;
    }

    // SET CHARACTER_SET_C
    private static int characterSetC(String stmt, int offset) {
        if (stmt.length() > offset + 1) {
            char c1 = stmt.charAt(++offset);
            switch (c1) {
                case 'o':
                case 'O':
                    return characterSetConnection(stmt, offset);
                case 'l':
                case 'L':
                    return characterSetClient(stmt, offset);
                default:
                    return OTHER;
            }
        }
        return OTHER;
    }

    // SET CHARACTER_SET_CONNECTION =
    private static int characterSetConnection(String stmt, int offset) {
        if (stmt.length() > offset + 8) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            if ((c1 == 'N' || c1 == 'n') && (c2 == 'N' || c2 == 'n') && (c3 == 'E' || c3 == 'e')
                && (c4 == 'C' || c4 == 'c') && (c5 == 'T' || c5 == 't') && (c6 == 'I' || c6 == 'i')
                && (c7 == 'O' || c7 == 'o') && (c8 == 'N' || c8 == 'n')) {
                while (stmt.length() > ++offset) {
                    switch (stmt.charAt(offset)) {
                        case ' ':
                        case '\r':
                        case '\n':
                        case '\t':
                            continue;
                        case '=':
                            while (stmt.length() > ++offset) {
                                switch (stmt.charAt(offset)) {
                                    case ' ':
                                    case '\r':
                                    case '\n':
                                    case '\t':
                                        continue;
                                    default:
                                        return (offset << 8) | CHARACTER_SET_CONNECTION;
                                }
                            }
                            return OTHER;
                        default:
                            return OTHER;
                    }
                }
            }
        }
        return OTHER;
    }

    // SET CHARACTER_SET_CLIENT =
    private static int characterSetClient(String stmt, int offset) {
        if (stmt.length() > offset + 4) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            if ((c1 == 'I' || c1 == 'i') && (c2 == 'E' || c2 == 'e') && (c3 == 'N' || c3 == 'n')
                && (c4 == 'T' || c4 == 't')) {
                while (stmt.length() > ++offset) {
                    switch (stmt.charAt(offset)) {
                        case ' ':
                        case '\r':
                        case '\n':
                        case '\t':
                            continue;
                        case '=':
                            while (stmt.length() > ++offset) {
                                switch (stmt.charAt(offset)) {
                                    case ' ':
                                    case '\r':
                                    case '\n':
                                    case '\t':
                                        continue;
                                    default:
                                        return (offset << 8) | CHARACTER_SET_CLIENT;
                                }
                            }
                            return OTHER;
                        default:
                            return OTHER;
                    }
                }
            }
        }
        return OTHER;
    }

    // SET SESSION' '
    // SET SQL_MODE
    private static int sCheck(String stmt, int offset) {
        if (stmt.length() > offset + 1) {
            int nextOffset = offset + 1;
            char c = stmt.charAt(nextOffset);
            if (c == 'E' || c == 'e') {
                return session(stmt, offset);
            } else if (c == 'Q' || c == 'q') {
                return sqlMode(stmt, offset);
            }
        }
        return OTHER;
    }

    // SET [SESSION] SQL_MODE = "mode"
    private static int sqlMode(String stmt, int offset) {
        if (stmt.length() > offset + 8) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);

            if ((c1 == 'Q' || c1 == 'q') && (c2 == 'L' || c2 == 'l') && (c3 == '_') && (c4 == 'M' || c4 == 'm')
                && (c5 == 'O' || c5 == 'o') && (c6 == 'D' || c6 == 'd') && (c7 == 'E' || c7 == 'e')) {
                while (stmt.length() > ++offset) {
                    switch (stmt.charAt(offset)) {
                        case ' ':
                        case '\r':
                        case '\n':
                        case '\t':
                            continue;
                        case '=':
                            while (stmt.length() > ++offset) {
                                switch (stmt.charAt(offset)) {
                                    case ' ':
                                    case '\r':
                                    case '\n':
                                    case '\t':
                                        continue;
                                    default:
                                        return (offset << 8) | SQL_MODE;
                                }
                            }
                            return OTHER;
                        default:
                            return OTHER;
                    }
                }
            }
            return OTHER;
        }
        return OTHER;
    }

    private static int session(String stmt, int offset) {
        if (stmt.length() > offset + 7) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            if ((c1 == 'E' || c1 == 'e') && (c2 == 'S' || c2 == 's') && (c3 == 'S' || c3 == 's')
                && (c4 == 'I' || c4 == 'i') && (c5 == 'O' || c5 == 'o') && (c6 == 'N' || c6 == 'n')
                && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;
                            case 'T':
                            case 't':
                                return transaction(stmt, offset);
                            case 'S':
                            case 's':
                                return sqlMode(stmt, offset);
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // SET [SESSION] TRANSACTION ISOLATION LEVEL
    private static int transaction(String stmt, int offset) {
        if (stmt.length() > offset + 11) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            char c9 = stmt.charAt(++offset);
            char c10 = stmt.charAt(++offset);
            if ((c1 == 'R' || c1 == 'r') && (c2 == 'A' || c2 == 'a') && (c3 == 'N' || c3 == 'n')
                && (c4 == 'S' || c4 == 's') && (c5 == 'A' || c5 == 'a') && (c6 == 'C' || c6 == 'c')
                && (c7 == 'T' || c7 == 't') && (c8 == 'I' || c8 == 'i') && (c9 == 'O' || c9 == 'o')
                && (c10 == 'N' || c10 == 'n') && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;

                            case 'P':
                            case 'p':
                                return policy(stmt, offset);
                            case 'I':
                            case 'i':
                                return isolation(stmt, offset);
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // set transaction policy 3
    private static int policy(String stmt, int offset) {
        if (stmt.length() > offset + 6) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);

            if ((c1 == 'O' || c1 == 'o') && (c2 == 'L' || c2 == 'l') && (c3 == 'I' || c3 == 'i')
                && (c4 == 'C' || c4 == 'c') && (c5 == 'Y' || c5 == 'y') && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;
                            case '1':
                                return TX_POLICY_1;
                            case '2':
                                return TX_POLICY_2;
                            case '3':
                                return TX_POLICY_3;
                            case '4':
                                return TX_POLICY_4;
                            case '5':
                                return TX_POLICY_5;
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // SET [SESSION] TRANSACTION ISOLATION LEVEL
    private static int isolation(String stmt, int offset) {
        if (stmt.length() > offset + 9) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            if ((c1 == 'S' || c1 == 's') && (c2 == 'O' || c2 == 'o') && (c3 == 'L' || c3 == 'l')
                && (c4 == 'A' || c4 == 'a') && (c5 == 'T' || c5 == 't') && (c6 == 'I' || c6 == 'i')
                && (c7 == 'O' || c7 == 'o') && (c8 == 'N' || c8 == 'n') && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;
                            case 'L':
                            case 'l':
                                return level(stmt, offset);
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // SET [SESSION] TRANSACTION ISOLATION LEVEL' '
    private static int level(String stmt, int offset) {
        if (stmt.length() > offset + 5) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            if ((c1 == 'E' || c1 == 'e') && (c2 == 'V' || c2 == 'v') && (c3 == 'E' || c3 == 'e')
                && (c4 == 'L' || c4 == 'l') && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;
                            case 'R':
                            case 'r':
                                return rCheck(stmt, offset);
                            case 'S':
                            case 's':
                                return serializable(stmt, offset);
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // SET [SESSION] TRANSACTION ISOLATION LEVEL SERIALIZABLE
    private static int serializable(String stmt, int offset) {
        if (stmt.length() > offset + 11) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            char c9 = stmt.charAt(++offset);
            char c10 = stmt.charAt(++offset);
            char c11 = stmt.charAt(++offset);
            if ((c1 == 'E' || c1 == 'e') && (c2 == 'R' || c2 == 'r') && (c3 == 'I' || c3 == 'i')
                && (c4 == 'A' || c4 == 'a') && (c5 == 'L' || c5 == 'l') && (c6 == 'I' || c6 == 'i')
                && (c7 == 'Z' || c7 == 'z') && (c8 == 'A' || c8 == 'a') && (c9 == 'B' || c9 == 'b')
                && (c10 == 'L' || c10 == 'l') && (c11 == 'E' || c11 == 'e')
                && (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset)))) {
                return TX_SERIALIZABLE;
            }
        }
        return OTHER;
    }

    // READ' '|REPEATABLE
    private static int rCheck(String stmt, int offset) {
        if (stmt.length() > ++offset) {
            switch (stmt.charAt(offset)) {
                case 'E':
                case 'e':
                    return eCheck(stmt, offset);
                default:
                    return OTHER;
            }
        }
        return OTHER;
    }

    // READ' '|REPEATABLE
    private static int eCheck(String stmt, int offset) {
        if (stmt.length() > ++offset) {
            switch (stmt.charAt(offset)) {
                case 'A':
                case 'a':
                    return aCheck(stmt, offset);
                case 'P':
                case 'p':
                    return pCheck(stmt, offset);
                default:
                    return OTHER;
            }
        }
        return OTHER;
    }

    // READ' '
    private static int aCheck(String stmt, int offset) {
        if (stmt.length() > offset + 2) {
            char c1 = stmt.charAt(++offset);
            if ((c1 == 'D' || c1 == 'd') && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;
                            case 'C':
                            case 'c':
                                return committed(stmt, offset);
                            case 'U':
                            case 'u':
                                return uncommitted(stmt, offset);
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // COMMITTED
    private static int committed(String stmt, int offset) {
        if (stmt.length() > offset + 8) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            if ((c1 == 'O' || c1 == 'o') && (c2 == 'M' || c2 == 'm') && (c3 == 'M' || c3 == 'm')
                && (c4 == 'I' || c4 == 'i') && (c5 == 'T' || c5 == 't') && (c6 == 'T' || c6 == 't')
                && (c7 == 'E' || c7 == 'e') && (c8 == 'D' || c8 == 'd')
                && (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset)))) {
                return TX_READ_COMMITTED;
            }
        }
        return OTHER;
    }

    // UNCOMMITTED
    private static int uncommitted(String stmt, int offset) {
        if (stmt.length() > offset + 10) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            char c8 = stmt.charAt(++offset);
            char c9 = stmt.charAt(++offset);
            char c10 = stmt.charAt(++offset);
            if ((c1 == 'N' || c1 == 'n') && (c2 == 'C' || c2 == 'c') && (c3 == 'O' || c3 == 'o')
                && (c4 == 'M' || c4 == 'm') && (c5 == 'M' || c5 == 'm') && (c6 == 'I' || c6 == 'i')
                && (c7 == 'T' || c7 == 't') && (c8 == 'T' || c8 == 't') && (c9 == 'E' || c9 == 'e')
                && (c10 == 'D' || c10 == 'd') && (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset)))) {
                return TX_READ_UNCOMMITTED;
            }
        }
        return OTHER;
    }

    // REPEATABLE
    private static int pCheck(String stmt, int offset) {
        if (stmt.length() > offset + 8) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            char c4 = stmt.charAt(++offset);
            char c5 = stmt.charAt(++offset);
            char c6 = stmt.charAt(++offset);
            char c7 = stmt.charAt(++offset);
            if ((c1 == 'E' || c1 == 'e') && (c2 == 'A' || c2 == 'a') && (c3 == 'T' || c3 == 't')
                && (c4 == 'A' || c4 == 'a') && (c5 == 'B' || c5 == 'b') && (c6 == 'L' || c6 == 'l')
                && (c7 == 'E' || c7 == 'e') && stmt.charAt(++offset) == ' ') {
                for (;;) {
                    if (stmt.length() > ++offset) {
                        switch (stmt.charAt(offset)) {
                            case ' ':
                            case '\r':
                            case '\n':
                            case '\t':
                                continue;
                            case 'R':
                            case 'r':
                                return prCheck(stmt, offset);
                            default:
                                return OTHER;
                        }
                    }
                    return OTHER;
                }
            }
        }
        return OTHER;
    }

    // READ
    private static int prCheck(String stmt, int offset) {
        if (stmt.length() > offset + 3) {
            char c1 = stmt.charAt(++offset);
            char c2 = stmt.charAt(++offset);
            char c3 = stmt.charAt(++offset);
            if ((c1 == 'E' || c1 == 'e') && (c2 == 'A' || c2 == 'a') && (c3 == 'D' || c3 == 'd')
                && (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset)))) {
                return TX_REPEATED_READ;
            }
        }
        return OTHER;
    }

}
